And if you've read the threads on this topic, I've at least twice pointed
to a set of Applescripts I wrote that do the job reasonably well. They
don't merge content of items, but they do export and import individual
items, and you can then resolve the differences by hand yourself.

Not perfect, but it works for me. I haven't had MobileMe syncing working
for a couple of years now, and I will use iCloud only as long as it is
free. The instant they plan to charge me anything for the bare-bones (no
pun intended) level of support, I'm dropping it completely and moving to a
DropBox or other solution.